What Optical Cables Are Used for 5G? Your Complete Buying Guide

■ Faster 5G Requires More, Better, and Smarter Fiber: What Optical Cables Are Used Today?

When 5G delivers a 10 Gbps download or connects a self-driving car in real time, the spotlight goes to wireless technology. But behind the scenes, one thing makes it all possible: optical fiber.

The reality is clear:

When it comes to 5G, more. better, and faster fibers are needed.

The purpose of high-quality optical cables in 5G, ensuring that speed, low latency, and reliability targets are met.

In this way we support the backbone of the 5G network.

This article breaks down:

• The exact types of optical cables used in real 5G deployments

• How they fit into the 5G network architecture

• What to consider when procuring fiber for 5G projects

• And answers to real-world questions engineers and buyers face

All based on current standards, field data, and global deployment practices.

■ Why Fiber Is Critical for 5G Performance

5G is wireless to the device — but wired at the infrastructure level.

Think of it like a highway:

• The last mile is wireless (air interface)

• But the long-distance route is fiber optics

According to the ITU-T, 5G base stations need:

• At least 10 Gbps backhaul capacity

• Latency below 100 microseconds for fronthaul links

• Support for 25G and 50G per wavelength in advanced setups

Only optical fiber can deliver this consistently.

Microwave and copper fall short in bandwidth and stability. That’s why leading operators like Verizon, China Mobile, and Deutsche Telekom all rely on fiber as the foundation of their 5G networks.

■ The 4 Main Optical Cables Used in 5G Networks

Not all fiber is the same. Here are the four most widely used types in 5G today — and where they’re deployed.

1. Single-Mode Fiber (SMF) – The Backbone of 5G

The Standard Compliance is: It is essential for all to have a proper assembling with the ITU-T G.65x standards.

Real-World Fact: Approximately 30 million km of G.652.D fiber have achieved deployment in China alone which was reported by MIIT for the year 2023.

Alternatively, the trial will kick off with new 5G microwave backhaul systems.

2. DWDM-Ready Fiber Systems – Multiply Your Capacity

• Technology: DWDM (Dense Wavelength Division Multiplexing)

• Function: this device sends up to 160 wavelengths through one fiber.

• Capacity: one fiber may transport up to 20 Tbps

• Used In: at the moment, core and aggregation networks are normally used cases.

Example: In a metropolitan area, a single DWDM can be utilized for thousands of 5G base stations serving.

• Vendor Platforms: Transport & Access – this option includes Ciena 6500, Huawei OSN 1800, Nokia PSE-6s.

• Fiber Type: fiber cables for G.652.D or G.654.E with low polarization mode dispersion (PMD) are the ones these products use.

3. Distribution Cables – For Last-Drop Connectivity

• Types: Butterfly (drop) cable, indoor riser cable

• Use Case: Connect street cabinets to 5G small cells or rooftop units

• Features:

• Lightweight

• Easy to install

• Resistant to bending and crushing

Common in dense cities like Shanghai, Seoul, and New York where space is limited.

4. Submarine Cables – The Global 5G Link

Even if you're using 5G locally, international content (like YouTube, AWS, or AI models) travels through undersea fiber.

Key systems supporting 5G global traffic:

• APG (Asia-Pacific Gateway)

• Japan-US Cable Network

• PEACE Cable (Pakistan-East Africa-Europe)

• Length: Up to 12,000 km

• Capacity: 24 Tbps+

• Latency: As low as 150 ms across the Pacific

■ How Fiber Fits Into 5G Network Architecture

5G splits its transport network into three layers — each with different fiber needs.

 Critical Warning: Fronthaul is the most sensitive. Even minor fiber damage or poor splicing can break 5G synchronization and degrade service.

■ Real Deployment Challenges (And How to Solve Them)

Here are common fiber-related issues in 5G rollouts — and how to avoid them.

• ❌ Problem: No Spare Fiber at Cell Site
  Many legacy sites have no dark fiber available.
  ✅ Solution: Deploy WDM-PON or micro-trenching to add new drops quickly.

• ❌ Problem: High Signal Loss Due to Bending
  Especially in rooftop or pole-mounted small cells.
  ✅ Solution: Use G.657.A2/B3 fiber and avoid sharp bends during installation.

• ❌ Problem: Mismatched Fiber Types in Links
  Mixing G.652 and G.654 causes reflection and loss.
  ✅ Solution: Maintain a fiber inventory log and label all cables clearly.

■ Procurement Guide: How to Buy Fiber for 5G

Buying fiber isn’t just about price. It’s about long-term performance and compatibility.

✅ 5 Key Questions to Ask Suppliers

1. Is the fiber ITU-T G.652.D or G.654.E certified?
   → Request test reports from third-party labs.

2. What is the actual attenuation at 1310 nm and 1550 nm?
   → Acceptable: ≤0.36 dB/km (1310nm), ≤0.20 dB/km (1550nm).

3. Is it bend-insensitive (G.657)?
   → Required for small cells and indoor units.

4. Can it support 25G or 50G wavelengths?
   → Needed for eCPRI-based fronthaul.

5. What’s the warranty and lifespan?
   → Look for 25-year warranty and manufacturer support.

■ Frequently Asked Questions (FAQ)

1. Q1: Can 5G run without fiber?
   No. While microwave or satellite can be used as backup, they lack the bandwidth and low latency 5G requires. Fiber is mandatory for full 5G performance.

2. Q2: How many fibers does a 5G base station need?
   Typically:So, 4 fibers minimum per site. High-density areas may use 8–12.

• 2 fibers for primary fronthaul (DU–AAU)

• 2 fibers for redundancy

3. Q3: Is existing 4G fiber enough for 5G?
   Sometimes — but often not.
   4G used ~1 Gbps per site. 5G needs 10–20x more bandwidth.
   If your fiber is old or shared, upgrade to DWDM-ready SMF.

4. Q4: What’s the cost of fiber deployment per km?
   Urban: $20,000–$50,000/km (trenching, permits, labor)
   Rural: $10,000–$25,000/km
   Micro-trenching can cut costs by 30–50%.

5. Q5: Who are the top fiber suppliers for 5G?
   Trusted brands include:Always verify compliance with ITU-T standards and request real test data.

• China: YOFC, Hengtong, ZTT

• USA: Corning, CommScope

• Europe: Prysmian, Nokia

• Japan: Fujikura, Sumitomo

■ Final Thought: Fiber Is Not Optional — It’s Strategic

5G is not just a radio upgrade.
It’s a full infrastructure transformation — and fiber is the foundation.

As one telecom CTO said:

“You can’t run a Formula 1 car on a bicycle path.”

So when planning your 5G rollout:

• Audit your fiber inventory first

• Choose the right type for each layer

• Plan for 5G-Advanced and 6G from day one

Because in the future of connectivity,
the fastest 5G network is the one built on the best fiber.

Contact us for more information

James is a technical manager and associate at Zion Communication. 

Specializes in Optical Fiber communications,  FTTH Solutions, 

Fiber optic cables,  ADSS cable, and ODN networks.

james@zion-communication.com

+86 13777460328